p983
Quinquennalia

Unsigned article on p983 of

QUINQUENNA′LIA,
were games instituted by Nero in A.D. 60, in imitation of the Greek festivals, and celebrated like the Greek πενταετηρίδες at the end of every four years:a
they consisted of musical, gymnastic, and equestrian contests, and were called Neronia (Suet. Ner. 12;
Tac. Ann.XIV.20;
Dion Cass. LXI.21). Suetonius and Tacitus (ll. cc.) say that such games were first introduced at Rome by Nero. The Quinquennalia, which had previously been instituted both in honour of Julius Caesar
(Dion Cass. XLIV.6)
and of Augustus (Id.LI.19; Suet. Aug.59,
98), were confined to the towns of Italy and the provinces. The Quinquennalia of Nero appear not to have been celebrated after his time, till they were revived again by Domitian in honour of the Capitoline Jupiter
(Suet. Dom. 4).

Thayer's Note:

a
If you have enough Latin to know that quinque means "five" and quinquennalis means "every five years", — leaving you puzzled that the Quinquennalia should be every four years — this note is for you.

The Romans counted everything inclusively, so that the festival cycle, to them, looked like this:

. . . 1 • 2 • 3 • 4 • 5 . . .

but if you look at it today's way, from 1 to 5 there are in fact only four years. We can read this same explanation, applied to the Olympic Games, in Isidore of Seville, writing in the 7th century A.D. — a transitional period in so many other and more important ways — for readers who were starting to think the way we do now: "quinquennale certamen, quattuor mediis annis vacantibus": "a quinquennalis contest, with four years in between"
(Orig.V.37.1). Similarly, in
Censorinus, de Die nataliXVIII.12, we have "Sed horum omnium pentaeteridas maxime notandis temporibus Graeci observant, id est quaternum annorum circuitus, quas vocant olympiadas. . ." ("but of all of these, the pentaeterids are the time-intervals most adverted to by the Greeks, that is cycles of four years, which they call Olympiads").

Don't just take my word for it, though. In his translation of Dio, for example — Xiphilinus actually — in that passage you went and looked at, Earnest Cary renders the Greek πενταετηρικόν (which also looks like "every five years") by "quadriennial".

Similarly, the Roman
Nundinae, an 8‑day period, derives its name from novem dies, "nine days"; and of course, the best-known example of what to us today seems an anomaly, the Easter triduum — the "three-day" span between the death of Christ and the Resurrection not quite a day and a half later.

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